Android is a Linux-based operating system designed primarily for touchscreen mobile devices such as smartphones and tablet computers, developed by Google in conjunction with the Open Handset Alliance. Initially developed by Android Inc, whom Google financially backed and later purchased in 2005, Android was unveiled in 2007 along with the founding of the Open Handset Alliance, a consortium of 86 hardware, software, and telecommunication companies devoted to advancing open standards for mobile devices.
Google releases the Android code as open-source, under the Apache License. The Android Open Source Project (AOSP), lead by Google, is tasked with the maintenance and further development of Android. Additionally, Android has a large community of developers writing applications (“apps”) that extend the functionality of devices. Developers write primarily in a customized version of Java, and apps can be downloaded from online stores such as Google Play (formerly Android Market), the app store run by Google, or third-party sites. In September 2012, there were more than 675,000 apps available for Android, and the estimated number of applications downloaded from Google Play was 25 billion.
The first Android-powered phone was sold in October 2008, and by the end of 2010 Android had become the world’s leading smartphone platform. It had a worldwide smartphone market share of 59% at the beginning of 2012, and as of third quarter 2012, there were 500 million devices activated and 1.3 million activations per day.
Android, Inc. was founded in Palo Alto, California, United States in October 2003 by Andy Rubin (co-founder of Danger), Rich Miner (co-founder of Wildfire Communications, Inc.), Nick Sears and Chris White.
Google acquired Android Inc. on August 17, 2005, making Android Inc. a wholly owned subsidiary of Google. Key employees of Android Inc., including Andy Rubin, Rich Miner and Chris White, stayed at the company after the acquisition. Not much was known about Android Inc. at the time of the acquisition, but many assumed that Google was planning to enter the mobile phone market with this move
Android has a release cycle where new major versions are released every six to nine months. Updates are typically incremental in nature, gradually improving the software on a regular schedule, rather than completely overhauling the system every two to three years which is common for desktop operating systems such as Windows. Between each major release, minor interim releases are made available as often as necessary to fix security issues and other software bugs. Most Android smartphones and tablets are capable of receiving updates “over-the-air” which allows the device to download and install updates without having to be connected to a PC.
Applications are usually developed in the Java language using the Android Software Development Kit, but other development tools are available, including a Native Development Kit for applications or extensions in C or C++, Google App Inventor, a visual environment for novice programmers and various cross platform mobile web applications frameworks.
Android applications run in a sandbox, an isolated area of the operating system that does not have access to the rest of the system’s resources, unless access permissions are granted by the user when the application is installed. Before installing an application, the Play Store displays all required permissions. A game may need to enable vibration, for example, but should not need to read messages or access the phonebook. After reviewing these permissions, the user can decide whether to install the application. The sandboxing and permissions system weakens the impact of vulnerabilities and bugs in applications, but developer confusion and limited documentation has resulted in applications routinely requesting unnecessary permissions, reducing its effectiveness. The complexity of inter-application communication implies Android may have opportunities to run unauthorized code.
Several security firms have released antivirus software for Android devices, in particular, Lookout Mobile Security, AVG Technologies, Avast!, F-Secure, Kaspersky, McAfee and Symantec. This software is ineffective as sandboxing also applies to such applications, limiting their ability to scan the deeper system for threats.
Android is under GNU so it minimizes the extra cost of purchasing a mobile.
Popularity of Android
|Drag and drop file management||no|
|Intelligent voice assistant||yes||yes|
with Google Now
|Core||Darwin||Linux||Windows NT||Windows CE 7|
via Camera Connection Kit